• Journal of Advanced Navigation Technology
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• v.28 no.2
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• pp.210-215
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• 2024

With increasing automation in ships and the development of autonomous ships, an IPMS (Integrated Platform Management System) in ship needs to integrate and process large amounts of real-time data from various equipment operating on different operating systems. A ship IPMS simulator based on data distribution service (DDS) was developed and its performance was evaluated to handle data processing similar in real ship environment. Errors were monitored while 1,000 topics/sec were asynchronously published and subscribed from data acquisitive units (DAUs) and an IPMS server operating on different operating systems. Except for the loss of some topics during the initial 4 seconds, topics were received without an error thereafter. The developed simulator demonstrates the feasibility of using DDS to integrate various control systems using different operating systems in actual ships.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.279-283
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• 1997

Membrane separation technology was applied to prepare high quality persimmon juice from persimmon, which is produced in large quantities in Korea. The influences of time, pressure, and temperature on permeate flux were studied during concentration by reverse osmosis. The chemical components of retentate were also analyzed. The permeate flux was higher as the operating temperature and pressure were increased, and was influenced more strongly by operating pressure than temperature. Maximum concentration by reverse osmosis employed in this study in the oBrix scale was about 30. Retention percentage of sugar in the persimmon juice which was concentrated by membrane separation system was more than 90% and was not influenced by operating conditions. Retention percentage of volatile components in the same process was more than 60%; it was increased as operating temperature was decreased and pressure was increased.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.153-163
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• 2016

Environments in nuclear power plants (NPPs) are changing as the design of instrumentation and control systems for NPPs is rapidly moving toward fully digital instrumentation and control, and modern computer techniques are gradually introduced into main control rooms (MCRs). Within the context of these environmental changes, the level of performance of operators in a digital MCR is a major concern. Situation awareness (SA), which is used within human factors research to explain to what extent operators of safety-critical systems know what is transpiring in the system and the environment, is considered a prerequisite factor to guarantee the safe operation of NPPs. However, the safe operation of NPPs can be guaranteed through a team effort. In this regard, the operating team's SA in a conventional and digital MCR should be measured in order to assess whether the new design features implemented in a digital MCR affect this parameter. This paper explains the team SA measurement method used in this study and the results of applying this measurement method to operating teams in different MCR environments. The paper also discusses several empirical lessons learned from the results.

• Journal of the Korea Society of Computer and Information
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• v.27 no.7
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• pp.65-73
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• 2022

Recently, as the Windows system supports the Windows subsystem for Linux (WSL), various researchers have studied to apply a docker container on various systems such as server systems, workstation system and so on. However, in various existing researchers, there is a lack of performance-related indicators to apply the system to each operating system (linux system and windows system). In this paper, we compared a performance comparison and analysis of container-based host operating systems. We configured experimental environments of operating systems for microsoft windows systems and linux systems based on a docker container support. In experimental results, the containers of linux systems reduced the average data latency of dataset 1-6 by 3.9%, 62.16%, 1552.38%, 7.27%, 60.83%, and 1567.2%, compared to the containers on microsoft windows systems.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1054-1057
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• 1995

The pollution-free secondary Li ion battery has been developed recently. However due to short history of Li ion battery, the standards for characterized assessments and standardized testing methods have not been prepared and established yet. Also, the researches have not been done systematically regarding the operating methods of these new type of batteries. Such limited knowledge of new batteries emphasizes the importance of development of characterized assessment and the operating methods.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1655-1658
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• 2004

In this paper, we design and implement remote servo motor control system with real-time micro embedded operating system. The system, where controller and camera image grabber are mounted, handles control commands transmitted from a remote PC web browser. A hard real-time servo motor driver running on the real-time micro embedded OS and then a digital control application which confirms precise sampling time intervals is constructed. Frame grabber images transmitted from camera are saved in a image data format to view on remote PC web browser.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.252-261
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• 2013

In this paper, a nonlinear adaptive damping controller based on radial basis function neural network (RBFNN), which can infinitely approximate to nonlinear system, is proposed for thyristor controlled series capacitor (TCSC). The proposed TCSC adaptive damping controller can not only have the characteristics of the conventional PID, but adjust the parameters of PID controller online using identified Jacobian information from RBFNN. Hence, it has strong adaptability to the variation of the system operating condition. The effectiveness of the proposed controller is tested on a two-machine five-bus power system and a four-machine two-area power system under different operating conditions in comparison with the lead-lag damping controller tuned by evolutionary algorithm (EA). Simulation results show that the proposed damping controller achieves good robust performance for damping the low frequency oscillations under different operating conditions and is superior to the lead-lag damping controller tuned by EA.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.5
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• pp.2084-2100
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• 2020

Operating system (OS) kernel function call graphs have been widely used in OS analysis and defense. However, most existing methods and tools for generating function call graphs are designed for application programs, and cannot be used for generating OS kernel function call graphs. This paper proposes a virtualization-based call graph generation method called Acquire in Trap (AIT). When target kernel functions are called, AIT dynamically initiates a system trap with the help of a virtualization technique. It then analyzes and records the calling relationships for trap handling by traversing the kernel stacks and the code space. Our experimental results show that the proposed method is feasible for both Linux and Windows OSs, including 32 and 64-bit versions, with high recall and precision rates. AIT is independent of the source code, compiler and OS kernel architecture, and is a universal method for generating OS kernel function call graphs.

• Knowledge Management Research
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• v.14 no.3
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• pp.37-54
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• 2013

Technology standards have gained importance as global market becomes more competitive. Since a technology acknowledged as a standard brings significant benefits to the developer firm, firms in the IT industry tend to pursue standardization for the technology, being it proprietary or open. However, the paths or strategic implications are seldom discussed in academia. Therefore, our study uses iPhone of Apple, one of the proprietary standards successes, to further understand corporate strategies over two standard choices. Our case study suggests that iPhone's entry timing was optimal for creating a new mobile environment. Design excellence and user-friendly interface increased networking effects and switching costs among consumers. Apple developed independent mobile operating system (iOS) through improvement on the existing operating system. During the process, Apple chose proprietary standard and, by installing the same UX on its sibling products such as iPod Touch or iPad, overcame the subsequent problems that might arise from the limited use of iOS. Based on the capability of concurrently developing both hardware and software, Apple connected operating system, machine, and contents, which deems to contribute to its proprietary standards success. We argue that this strategy should be considered for firms which plan proprietary standard strategy.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.2
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• pp.139-146
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• 2011

The ventilation performance of a vertical exhaust duct system in the high riser public house has been evaluated by a commercial software, Fluid Flow, which solves pressure losses through the duct system including bathroom fans and a hybrid roof fan. During the numerical simulations, outdoor wind condition and stack effects in summer and winter were considered as well as the operating conditions of a basement damper and the roof fan. The results show that the bathroom ventilation in summer is the most unsatisfactory. The opening of the basement damper has a problem that the polluted air in the lower floors is exhausted to the underground parking lot, not to the rooftop. If the basement damper is closed, the exhaust flow rate in the lower floors is not sufficient due to the strong flow resistance in the long vertical duct even though the roof fan is under operating.